Enthalpies of formation of the carbides of aluminium and beryllium

Abstract

The Enthalpies of formation of the carbides of aluminium and beryllium have been determined by comparing their heats of dissolution in hydrochloric acid at 100°C with those of the constituent metals. The experiments were carried out in closed glass vessels inside a calorimeter. The values obtained are: ΔH°_f298,(Al₄C₃)=–49.54 ± 0.57 kcal/mol (–207.3 ± 2.3 kJ/mol) and, ΔH°_f298,(Be₂C)=–27.96 ± 0.21 kcal/mol (–117.0 ± 0.8 kJ/mol).